package com.gouying.web.interceptor;

import com.gouying.common.constant.AuthServerConstant;
import com.gouying.common.constant.CartConstant;
import com.gouying.vo.MemberResponseVo;
import com.gouying.web.vo.UserInfoTo;
import org.apache.commons.lang.StringUtils;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.util.UUID;


/**
 * @author ly
 */
public class CartInterceptor implements HandlerInterceptor {

    public static ThreadLocal<UserInfoTo> threadLocal = new ThreadLocal<>();

    /**
     * 在目标方法之前，判断用户的登录状态，并封装传递给controller目标请求
     */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        UserInfoTo userInfoTo = new UserInfoTo();
        HttpSession session = request.getSession();
        MemberResponseVo member = (MemberResponseVo) session.getAttribute(AuthServerConstant.LOGIN_USER);
        if (member != null) {
            //用户登录了,给他设置一个user-key
            userInfoTo.setUserId(member.getId());
        }
        Cookie[] cookies = request.getCookies();
        if (cookies != null && cookies.length > 0) {
            for (Cookie cookie : cookies) {
                //user-key
                String name = cookie.getName();
                if (name.equals(CartConstant.TEMP_USER_COOKIE_NAME)) {
                    userInfoTo.setUserKey(cookie.getValue());
                    userInfoTo.setTempUser(true);
                }
            }
        }
        //如果没有临时用户一定分配一个临时用户
        if (StringUtils.isEmpty(userInfoTo.getUserKey())) {
            String uuid = UUID.randomUUID().toString();
            userInfoTo.setUserKey(uuid);
        }
        //目标方法执行之前，通过同一个线程携带数据
        threadLocal.set(userInfoTo);
        //全部放行
        return true;
    }

    /**
     * 业务执行之后发放cookie，分配临时用户，让浏览器保存
     */
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        UserInfoTo userInfoTo = threadLocal.get();
        //如果没有临时用户一定保存一个临时用户
        if (!userInfoTo.isTempUser()) {
            //持续延迟临时用户的过期时间
            Cookie cookie = new Cookie(CartConstant.TEMP_USER_COOKIE_NAME, userInfoTo.getUserKey());
            //设置作用域
            cookie.setDomain("gulimall.com");
            //设置过期
            cookie.setMaxAge(CartConstant.TEMP_USER_COOKIE_TIMEOUT);
            response.addCookie(cookie);
        }
    }
}
